The president reportedly spoke for Mrs Trump before the procedure and talked to her doctor immediately afterwards.

US President Donald trump departs from the South Lawn of the White House to visit Melania Trump in hospital Credit:
MANDEL NGAN/AFP

The seriousness of the kidney issue was unclear, with aides to the first lady saying little beyond the fact that she was “doing well” after the operation.

The news came a surprise to Washington and did not leak from the White House before it was announced on Monday morning.

Melania Trump is Donald Trump's third wife and is a former modelCredit:
REUTERS/Kevin Lamarque

Anita McBride, former chief of staff to George W Bush’s wife Laura, said she could understand the decision to only put limited information into the public domain.

“I can completely understand their need and desire to keep it as tight as possible,” Ms McBride said on CNN, adding that she took a similar approach to Mrs Bush's health concerns.

She said there is a difference between the public’s “right to know and need to know”, noting that voters did not have the same right to know about the president wife’s health as they did for the president.

Douglas Brinkley, a presidential historian, said on CNN that the hospital treating Mrs Trump had the “best doctors in the country”, suggesting Mrs Trump would be in safe hands.

He noted that she is not the first wife of a president to undergo an operation while living in the White House.

Ronald Reagan’s wife Nancy was diagnosed with breast cancer and had a 50-minute operation in 1987. Gerald Ford’s wife Betty also had breast cancer.